Log4j2内存泄漏

Question

我到处寻找解决方案，现在我开始怀疑它是否真的是一个问题。

我正在将log4j2作为记录器引入我的应用程序，当我这样做时，在重新加载，取消部署或停止Tomcat服务器8.5.24时，会留下内存泄漏，只有在我将记录器引入代码后才会发生。

我在pom.xml的依赖：

<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-api</artifactId>
    <version>2.10.0</version>
</dependency>
<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-core</artifactId>
    <version>2.10.0</version>
</dependency>

我的WebServlet：

import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.LogManager;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

@WebServlet(name = "Servlet", urlPatterns = {"/servlet"}, loadOnStartup = 1)
public class Servlet extends HttpServlet {

    private final Logger logger = LogManager.getLogger(Servlet.class);

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        logger.info("doGet");

        PrintWriter out = response.getWriter();
        out.print("Servlet loaded");
        out.flush();
        out.close();
    }

}

我的log4j2.xml：

<?xml version="1.0" encoding="UTF-8"?>
<Configuration>
    <Appenders>
        <Console name="Console">
            <PatternLayout pattern="%d %p %c %m%n" />
        </Console>
        <File name="File" bufferedIO="true" fileName="logs/log4j2-file-sync-${date:HH:MM:ss.SSS}.log">
            <PatternLayout pattern="%d %p %c %m%n" />
        </File>
    </Appenders>
    <Loggers>
        <Root level="all" includeLocation="false">
            <AppenderRef ref="Console" />
            <AppenderRef ref="File" />
        </Root>
    </Loggers>
</Configuration>

这是我得到的错误：

The following web applications were stopped (reloaded, undeployed), but their
classes from previous runs are still loaded in memory, thus causing a memory
leak (use a profiler to confirm):
/myapp

Answer 1

感谢来自评论的@RemkoPopma和来自Tomcat JIRA董事会的@RalphGoers的建议，回答我自己的问题。

我在pom.xml中只需要以下依赖项，它还会导入core和api，并处理Log4J2的正常关闭。

<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-web</artifactId>
    <version>2.10.0</version>
</dependency>

可以找到此依赖项的特定文档

https://logging.apache.org/log4j/2.x/manual/webapp.html